^^^^^AZ STP blue cans have never been Purolator made, at least in this area. Before the Fram/Champ alliance, always all Champ Labs made, very similar to the old WM Super Tech line. Then after Fram-Champ (fram filtration) got together, they became a combination of Fram/Champ filters. Now after the fram-champ separation at AZ here at least, they have remained as such. That explained in this recent post HERE

Several Puro made AZ STP blue can anecdotes have shown up here in last year or two. Iirc, at one point the fram rep said they were all going to Puro made, then early this year said that they were all being offshored. Neither has happened.

To topic bypass, if OP interested in a little more detailed info on bypass function, Baldwin link basic explanation of function. It appears to show a thread end bypass vs dome end in topic but idea is the same. Just bypass opens at dome end in topic filter.

I'd like to point out the lack of comments regarding two things:Leaf spring.BP construction.

If this were a Fram someone would whine about the type of button bypass, and the leaf spring. It's not a Fram, so these go unchallendged?

To be clear, I think the leaf spring and button BP are perfectly acceptable. i am not complaining on that plane.

I just find the lack of complaints for the very same features which exist in another product so often ridiculed a bit of hypocrisy by some.

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The act of preventative maintenance, in and of itself, is FAR MORE important than brand/grade/base choices among lubes and filters. - under maintaining something is akin to abuse/neglect; that can kill equipment by shortening the lifespan- over maintaining something has never been proven to be anything but a waste of time and money